Deep Vein Thrombosis Diagnosis Venography

Diagnosing deep vein thrombosis (DVT) can be difficult and time consuming, as some commonly used diagnostic tests are ineffective at detecting this condition. For example, the plethysmography, a test that measures the blood pressure in different parts of your body, is known to regularly return false positives. However, because the plethysmography is a relatively inexpensive, non-invasive test, doctors generally couple it with one or more other diagnostic tests, such as a venography.

How a Venography Works

A venography, one of the most effective tools for diagnosing DVT, is an X-ray taken after dye has been injected into a patient’s veins. A venography points out blood clots associated with DVT by revealing areas in which the dye has obstructed flow. This test best detects clots in the calf and the thigh.

During a venography, a patient receives local anesthesia before the doctor injects a radioactive dye into the patient’s body through a catheter, usually situated in a vein on his foot. Patients generally lie on a table, possibly at an angle, to help the dye flow through the veins. A technician will then take X-rays to assess how the dye moves through the patient’s body. Patients sometimes feel uncomfortable as the dye floats into their veins.

Doctors recommend that patients do not participate in strenuous activities after having a venography, which takes about half an hour to complete unless you run into complications. Patients do not have to stay in hospitals after the procedure.

Pros and Cons of Venography

While a venography is highly effective at detecting DVT, the test can also help doctors identify tumors or inflamed tissues that are impairing a patient’s health.

The cons associated having a venography revolve around the cost of the procedure and potential complications. Along with the price of the anesthesia, a venography needs to be performed by highly trained technicians, which also don’t come cheap.

Another potential downside of a venography is the fact that complications, such as infection where the catheter is inserted and allergic reactions to the dye, can arise. Similarly, people who have kidney problems or diabetes should make sure that their physicians are aware of these conditions before agreeing to have a venography, as both conditions can create complications.

Venography vs. Other DVT Tests

Ultrasonography, the most commonly used test to diagnose DVT, is not always the best method of finding clots. Out of the two types ultrasonography tests used today, duplex and Doppler, Doppler tends to be more accurate because it renders colored images.

The advantages of ultrasonography are that ultrasonography is less expensive than venography and is also non-invasive. However, because it can be difficult to interpret, ultrasonography is also less effective in determining whether a patient has clots in the calf and pelvis.

As a result, venography is often used when ultrasonography tests results seem to be inconclusive. Although it is highly effective, venography isn’t used more frequently because it is expensive. Similarly, the test cannot be repeated frequently because it uses radioactive materials.

Talk to your doctor and make sure that you fully understand all of the advantages and disadvantages associated with venography before going through this diagnostic procedure.

Resources

Answers.com (2007). Body Plethysmography. Retrieved July 18, 2007, from the Answers.com Web site: http://www.answers.com/topic/body-plethysmography?cat=health.

American Academy of Orthopaedic Surgeons (2007). Deep Vein Thrombosis. Retrieved July 19, 2007, from the AAOS Web site: http://orthoinfo.aaos.org/fact/thr_report.cfm?Thread_ID=264.

Bupa (2006). Deep Vein Thrombosis. Retrieved July 18, 2007, from the Bupa Web site: http://hcd2.bupa.co.uk/fact_sheets/mosby_factsheets/Deep_Vein_Thrombosis.html.

Cantwell, Colin Patrick et. al. (2006). MR Venography with True Fast Imaging with Steady-state Precession for Suspected Lowerlimb Deep Vein Thrombosis. Retrieved July 19, 2007, from the Science Direct Web site: http://www.sciencedirect.comscience_ob=ArticleURL